WORCESTER 
The jury in the Felix Rodriguez murder trial heard testimony Tuesday about violent encounters Willie Jackson III had with police before suffering a fatal stab wound in 2009, allegedly at the hands of Mr. Rodriguez.

Investigators said Mr. Rodriguez, 54, told them he stabbed Mr. Jackson in the chest on the night of Dec. 22, 2009, but only after being attacked by the 25-year-old and another man, Tyrone Harris. The stabbing occurred in a makeshift basement apartment at 25 Charlton St.

Mr. Rodriguez told police he and the two men with whom he fought were all high on crack cocaine at the time.

Mr. Harris, 47, disputed Mr. Rodriguez’s account of the stabbing.

He testified last week that Mr. Rodriguez took off his clothes, brandished a knife and indicated he wanted to have sex with a woman who was present shortly after he arrived at the apartment. Mr. Harris said Mr. Jackson grabbed the knife from Mr. Rodriguez’s hand and threw it across the room.

Somehow, Mr. Rodriguez got the knife back and stabbed Mr. Jackson, according to Mr. Harris.

Mr. Rodriguez’s lawyer, John J. Roemer, then called a succession of Worcester police officers to the witness stand in an effort to show that Mr. Jackson had a propensity for violent behavior.

Officer Joseph Essex testified that he was involved in the Oct. 11, 2006, arrest of Mr. Jackson for trespassing. Officer Essex said Mr. Jackson began yelling after being taken into custody, tried to spit on another officer, then threatened to kill that officer.

Officer Darnell McGee told the jury that Mr. Jackson became “argumentative” when he went to a local supermarket on July 22, 2009, to arrest him for shoplifting. He said Mr. Jackson struggled and refused to place his hands behind his back when he tried to handcuff him.

After being subdued and taken outside, Mr. Jackson began yelling and spitting at people, according to Officer McGee, who said Mr. Jackson was later convicted of resisting arrest in the case.

A third police officer, Paul Noone, said he and other vice squad officers became involved in a struggle with Mr. Jackson when they went to an apartment on Gates Street March 2, 2006, to execute a search warrant.

Officer Noone said Mr. Jackson was punching and kicking while being subdued and was later found guilty of resisting arrest.

Under cross-examination by Mr. Dillon, the officers said they were not in fear for their lives or personal safety at the time of the arrests.

Psychologist Paul A. Spiers, who was hired by the defense to evaluate Mr. Rodriguez, testified that he is a man of “extremely limited intellect” with a history of anxiety, depression and alcoholism.

He testified that Mr. Rodriguez was hospitalized a short time before the stabbing because of depression and suicidal thoughts and said he was prescribed medications, which he did not take after his release from the hospital because he could not afford to pay for them.

Under questioning by Mr. Roemer, Mr. Spiers said it was likely that Mr. Rodriguez was in an “impulsive mode of behavior” on the night of the stabbing and that his mental state precluded him from foreseeing the consequences of his actions.

Under cross-examination by Mr. Dillon, Mr. Spiers acknowledged that he did not examine Mr. Rodriguez until nearly three years after the stabbing.